Liquid petroleum gas vaporizer



3 Sheets-Sheet 1 INVENTOR ATTORNEY C. E. GOLDEN LIQUID PETROLEUM GAS VAPORIZER Original Filed Feb. 18, 1958 illlllll Oct. 2%, 1964 620 15 fia/devz r- Wal Oct. 20, 1964 c. GOLDEN LIQUID PETROLEUM GAS VAPORIZER Original Filed Feb. 18, 1958 3 Sheets-Sheet 2 R Y O E W "W 9 a M A ,7 M J E 0% u 0 %FZEEE%/ w W. m .i 5 f. mo l b r i K i V//% 5 A I W Y 5 My u 5 6 g i w w w ,m iii 1 J J I i 7 w M W [E 1 Q A O H 8 w a 1 H 9 7 d w H lw 0 3 fl 2 w 3 OJ H 3 z y fl m m E g M 5% mm! w w M m Oct. 20, 1964 c. E. GOLDEN LIQUID PETROLEUM GAS VAPORIZER Original Filed Feb. 18. 1958 3 Sheets-Sheet 3 INVENTOR far/ 60/45 BY W w @h ATTORNEY United States Patent 3,153,439 LIQUID PETRGLEUM GA VAPQREZER Carl ll. Golden, 2415 Hale Drive, Burlingame, Calif. Continuation oi abandoned application Ser. No. 715,948, Feb. 18, 1953. This application June 4, 1962, Ser. No.

Claims. (Ql. TSS-F-SS) burned in. vapor form upon the admixture of air. The

usual gases of this sort are propane and butane. These gasesare customarily stored under pressure and at atmospheric temperature conditions are liquid. In order that they may be burned well, it is necessary to heat and vaporize; them. This'has been done in a variety-pt ways and it is a prime object of'the present invention to provide an improved vaporizer for this purpose.

Another object of the invention is to provide a liquid petroleum gas vaporizer which is substantially automatic inv-its operation and is effective under widely ditierent operating conditions to give a satisfactory and safe result.

Another object-of the invention is to provide a liquid petroleum gas vaporizer having very close control over the temperature of the issuing vapor.

Another object of the invention is to provide a liquid petroleum gas vaporizer in which a number of safety features are incorporated.

Another object of the invention isto provide a liquid petroleum gas vaporizer'which can operate unattended and satisfactorily over along period of time despite wide variations and even abnormalities in the operating conditions.

Another object ofthe invention is to provide a liquid petroleum gas vaporizer which can readily be fabricated, sold and utilized as a packaged unit.

Another object of'the invention is to provide a liquid petroleum gas vaporizer economical of materials in its construction and efiectively utilizing the heat available for vaporizing.

-A still further object of the'inventionis to provide a liquid petroleum gas vaporizer relatively simple and economical to build and for that reason-utlizing in many instances standard components.

Another. object of the invention is to provide a liquid petroleum gas vaporizer'whieh canreadily be serviced if necessary and maintained in a-satisfactory operating condition.

Other objects, together with the foregoing, are attained in the embodiments of the invention described in-the accompanying description and illustrated in the accompanying drawings in which:

FIGURE 1 is-a cross section through'aliquid petroleum gas vaporizer constructed accordance with the invention, the plane of section for the most part being just within the enclosing outer casing, but for some portions being on a diametrical, vertical plane showing some of'the interior construction;

FIGURE 2 is a detail showing in side elevation the exterior of thechamber mechanism, with portions broken away to show certainoi the interior features in'diametrical' cross section;

FIGURE 3 is a cross section similar to FIGURE 1 but 'taken at substantially 90 thereto and showing the in 3,i53,439 FatentedQct. 2.0, 1954 FIGURE 5 is a cross section the plane o f which is indicated bythe line 55 of FIGURE 3;

FIGURE 6 is a diagrammatic cross section showing. modified form of construction;

FIGURE 7 is a diagrammatic cross section: showing another-modifiedform of construction;

FIGURE 8 is a cross section througha modified form of pressure equalizing valve.

The liquid petroleum gas vaporizerppursuant to the invention can be fabricated in a number of different ways depending upon its especial environment, capacity and use, but it has successfully been incorporated in the forms shown herein.

With especial reference to FIGURES 1 to 5, the vaporizer includes on the exterior ametallic housing or casing 6 having a suitable support portion 7 transmitting the weight of the mechanism to the. floor .and includes a bottom wall 8 and an intermediate, annular wall 9 having a central hole iii and spaced above the bottom wall to leave a lower compartment 11 open .to the atmosphere. The casing also includes a top wall 12 closing the upper portion of the casing to define an upper compartment 13 open to. the atmosphere through. a.vent 14. Theupright casing 6 serves as asupporting frame and as a container for the rest of the mechanism. Borne on the lower wall SWithin the compartment 11 is a vaporizing burner 17 having a foot 18 removably secured to a a supporting bracket 19. Hooks 21 fastened to the intermediate wall 9 assist in holding the burner in place.

Extending above the intermediate wall 9 and disposed substantially vertically above the burner 17 are the outer wall 23 and the inner wall 24 of a jacket, generally designated 26. Thelower end of the jacket is preferably formed by the intermediate wall 9 whereas the top of the jacket is partially closed bya ring 27. The outer wall 23 extends upwardly above. the ring and the inner wall 24 stops at. the ring so that an opening 28 isleft for free communication between. the interior of the jacket and the vent 14; Thermal insulating material 29 is confined by the outer wall 23, the inner wall 24, the annular intermediate wall 9 andthe top ring 27 so that the'jacket serves as agood thermal insulating medium.

Coaxially disposed within the jacket 26 is a chamber 31 having a cylindrical side Wall 32 spaced fromthe interior wall 24 of the jacket to leave an annularpassageway 33. The chamber is closed at the bottom by a lower closure disc34 and is similarly closed at the topby anupper closure disc 36. On the outside of the wall32 are fins 37 of good. heat transferringmaterial well bonded to the wall 32 for heat transfer purposes, the fins 37 having angularly disposed ends 38 to assist in defining a tortuous flow passageway. Located within the chamber 31 is a metal tube 41 concentricallydisposedand blocked at its upper end by a plate 42.

When the burner 17 is in operation, the products of combustion emanating therefrom rise through the annular hole lll'and flow upwardly within the jacket 26 and through the passageway 33 over the fins 37. Heat is prevented from going outwardly by the insulation in the jacket, but is transferred inwardly to the chamber 31. The spent products of combustion travel upwardly through the annular opening 28 and out the vent '14.

To take advantage of the supply of heat, the liquid petroleum gas is introduced from any suitable source, not shown. The liquid travels through a pipe 51 having an elbow 52 so that the: discharge is axially downward through the top plate 36 into the upper portion of the chamber 31. The discharged material is deflected or directed by the top plate 42 of the tube 41 to flow in very close contact with the interior of the chamber wall 32. There is thus a very efiective'heat transfer from the prodnets of combustion going upwardly through the channel 33 to the liquid petroleum gas flowing downwardly on the inside of the wall 32 or in the annular space 53 occurring between the wall 32 and the tube 41.

As the liquid absorbs heat, it is vaporized into gaseous form. Being blocked at the bottom by the closure disc 34, the gas then rises upwardly within the tube 41 toward the top beneath the plate 42. Unvaporized liquid separates out and vaporizes on the disc 34. Under abnormal conditions, excessive liquid on the disc 34 can be drained through a normally plugged drain pipe 55. The gas at the top of the tube 41 discharges from the interior of the tube 41 through a conduit 54 extending radially from within the tube to a point outside of the jacket 26 the conduit 54 passing across the annular passage 53 and across the annular passageway 33.

On the outside of the jacket, the conduit 54 is joined to a cross 66 or four-way connection. One arm of the cross 66 is connected by a pipe 67 to a relief valve 08 (FIGURE 3). This is a standard relief valve installed at a remote point and is set to open under an excessive pressure. That is, the normally closed valve is automatically opened when the pressure of the gas within the system, as

evidenced at the relief valve 68, is excessive. The pressure in the system cannot exceed the desired or predetermined amount.

Another branch of the cross 66 is joined to a T 71 not only forming a gas conduit but particularly serving to house a temperature responsive valve. For that reason a pipe 72 leading away from the T 71 is provided on its upper end with a seat 73 (FIGURE Opposite the seat is disposed a poppet valve 74 having a stem '76 slidably disposed within a sleeve 77 screwed into a plug '73 closing the upper end of the T '71. A spring 79 is interposed between the plug 73 and the valve 741- and urges the valve toward closed position on the seat 73. When the valve is closed there can be no flow from the cross 66 into the pipe 72.

Since for normal operation the valve '74 is necessarily open, the upper end of the stem 7s is provided with ribs 81 embedded in a thermally fusible material 82 solid under ordinary conditions and partly interlocked with grooves 83 in the plug 78. A closure 84- affords access to the interior of the plug 78. While the material 82 is solid, the valve is firmly held in its open position.

With this mechanism, flow through the T 71 is substantially unencumbered under normal conditions, but since the T is located close to the upper portion of the jacket 26 and is in reasonably good thermal relationship therewith, upon the occurence of any excessive temperature either from within the jacket or from the surroundings, then the fusible material 82 melts and frees the stem 76 so that the spring '79 closes the valve 74. This prevents any flow through the pipe 72 and is a safety shut off actuated by excessive temperature.

Fluid flowing downwardly through the pipe 72 enters a T 86. One branch 87 of the T 86 is joined to the lower portion 88 of a tank, generally designated 89, completed by a cap 91 firmly screwed onto the lower portion 88. The cap 91 is joined to a T 92 extending to an outlet conduit 03 extending to the point of use of the vapor. Within the tank 89 (FIGURE 4) there is provided a mechanism for shutting ofif the operation in the event the system b comes overloaded so that liquid rather than vapor is passed through the pipe 72. It is preferred to shut the system off rather than to permit any overload or excess liquid to get into the discharge pipe 03. For that reason, the cap 91 is provided within the tank with a suitable valve seat 94 preferably made of rubber-like material such as neoprene held in position by a disc '96 and fastenings 97. Depending from the disc 96 is a shell 98 having a bottom plate 99 secured thereto and having perforations 101 at suitable intervals.

Located within the shell 98 is a buoyant ball 102 or float which, when the tank 89 is empty of liquid, rests on the bottom plate 99. Liquid flowing into the tank and rising therein sufliciently to flow through the apertures 101 into the shell 98 lifts the ball 102 into an upper position (shown by the dotted lines in FIGURE 4) protruding through the plate 96 and seating on the seat 94. The ball when so raised blocks outward flow from the tank 89 into the T 92 and into the discharge pipe 93.

Means are provided for unseating the ball 102 after it has been closed by liquid. After such closure occurs there is a substantial pressure difference between the interior of the tank 89 and the discharge pipe 93, the tank having the higher pressure. To permit restoration of the position of the ball 102, the T 86 is joined to the T 92 by means of a conduit 103 extending to a hand valve 104. A conduit 105 and a T 106 connect the valve 104 to the T 92.

Under usual operating conditions the valve 104 is closed and a pressure differential can readilyexist between the interior of the tank 89 and the pipe 93. However, when the tank 89 is full of liquid and after the system has been shut down by the ball 102 blocking flow out of the tank 80, the operator can manually open the valve 104. This permits an equalization of pressure on opposite sides of the valve seat 94. To assist the operator in determining the pressure, there is provided a gage 111 fastened into the pipe 105. The float or ball 102 then falls freely by gravity back into its lower position, as shown by the full lines in FIGURE 4, and the mechanism is then ready for subsequent operation. Excess liquid can be drained through a normally closed valve 107 connected to the T 103 by a conduit 108. A safety plug 109 in the outlet of the valve 107 is removed before such drainage and preferably is restored thereafter.

To equalize the pressure through the pipe 105, a valve 104a can be used instead of the valve 104. This is shown in FIGURE 8 and includes a nipple 105a joined to the T 103. Within the nipple is a standard pneumatic tire inflation valve core 100a having a normally closed valve opened by depression of a stem 107a. The nipple is fastened to a T 108a having an outlet 10% joined to the pipe 105. Within the T 108a is a rod 110a guided in a nipple 111a normally closed by a cap 112a. A sealing ring 11301 precludes leakage. A spring 114a urges the rod away from the stem 107a. The operator removes the cap 112a and manually depresses the rod 110a against the urgency of the spring 114a to abut and depress the stem 107a and so open the valve. Normally, it requires only a momentary opening of the valve to equalize the pressure, following which therod 110a is released and the springs restore the parts to closed condition. The operator cannot leave this valve open inadvertently.

Some of the vapor or gas normaly manufactured is not discharged through the outlet pipe 93, but is utilized to supply the burner 17. For that reason the T 106 has a branch connected through a pressure reducing valve 112 to a T 113. The pressure reducing Valve 112 is of any standard sort and permits the throttling of flow so that its outlet pressure is less than that at the normal outlet 93.

From the connector 113 the piping extends to a T 114 (FIGURE 1) arranged vertically and having a depending sump pipe 116 connected to a blow-off valve 117. In the event any condensation takes place within the flowing gas or if any liquid should be entrapped and carried along, it tends to fall and collect within the sump pipe 116. The valve 117 can be opened and the liquid discharged from time to time, if necessary.

The other branch of the T 114 is connected by a tube 118 to a fitting 119 extending into a control mechanism 121. This control is a substantially standard unit having manual setting knobs 122 and 123 thereon. The control is primarily actuated by a thermostatic element 124 which is a temperature responsive device coaxially disposed within the pipe 54 and passing through the cross 66 into the unit 121. The thermostatic element 124 is thus subject to. the temperature. existing within the upper portion of the tube 41. It is also somewhat affected by the temperature ofthe incoming, material flowing in the annular space 53andis subject to the temperature of the substantially-spent products of combustionpassing through 'the annular space 2 8.

At low temperatures the thermostat permits substantiallya .fullflow of gas from the tube 118 into another tube 126 extending downwardly within the housing 6' and joined to'a leg 127 of the burner 17, so that normally theburner is well-supplied with gas. Preferably, this gas is not mixed with air within the burner 17, but rather 1 is discharged undiluted in "an upward and inward direc- IIQIIlhITOUgh jets 128 arranged around the interior of the burner 17 The resulting flame is rich ingas and picks up combustion airffrom the compartment 11. Thusthe flames from the jets 128" impinge gently on the exterior ofthe 'chamber. 31 and rise upwardly along the wall of thecharnber with a sort of scrubbing action. so that there is a good heat transfer without'any excessive, blast or oxidizingaction. Since the rising gas picks up its combustionair-as it ascends, the flame from the'jets 128'is relativelylong axially and" extends well up into the annular space 33. This also assists in affording good heat transferfrom the burning fuel to the incoming liquid on the other side of the'wall lalof the chamber 31.

Whenever the temperature of the thermostat 124'rises above-apredetermined value asset by theknob 123, the

I thermostaticvalve moves toward closed position and flow of gas through the main supply line 126 -to the burner interrupted until an operator resets the mechanism upon rekindling the pilot light. 7 v a A modified portion ofthe structure is" shown in FIG- URE 6, the remaining parts of. the device being unchanged. In thisinstance the chamberwall 32a is sealed atZthetopgto a closure plate36a through which the inlet pipe 52 extends and is sealed at the bottom to a closure plate 34a through which a pipe 55a extends. This pipe is connected to one branch of a cross 66a from another branch of which a pipe 72a leads ultimately to the gas outlet. The cross 66a also accommodates a thermostat tube 54a within which a thermostat well 124a isinstalled. A bulb thermostat 125a is installed within the well 124a,

preferably embedded in good heat transfer material, not

with a small aperture 44a in it.

In the operation of this device, when excessive or unevaporated liquid from the inlet 52 gathers in the bottom of the chamber 32a, it can escape only slowly through the small aperture 44a. Its pressure tends to rise and to drive some of the liquid through the pipe 55a and through the cross 6611 into the tube 54a. This closely surrounds the thermostat and brings the fire on full so as to evaporate the excess liquid. The liquid from the tube 54a discharges into the tube 41a for evaporation, and when evaporated flows with other gas from the tube 41a out through the thermostat tube 54a and the cross 66a to the outlet pipe 72a.

Another modified portion of the structure is shown in FIGURE 7 In this instance, the chamber wall 32b is sealed at the top to a closure plate 36b through which the and is closed at the top by a plate 42b'and at the bottom by a plate 43b. There is a small. aperture 44b in the plate 43!) and upstanding from the. plate is a pipe 55b ending close to a thermostat124b passing through a tube 54b joined to a cross- 66b. Anoutlet pipe 72a extends from the cross which is otherwise closed.

In the operation of thisarrangement under normal, steady conditions, liquid enters through the pipe SZ-and is supplied with sufificient heat to..be completely evaporated within thechamber defined by the wall 321) and-so to be. converted ima as. Because of the normalpressure drop. across the apparatus betweentthe higher pressure inlet pipe 52 and thevlowert pressure outlet pipe 72a, thegasfiows upwardly-ahroughthe aperture 44b and-the pipe 55b around the tube ofthe-thermostat-l24b. Thegas flows out of the-cup l25b=and out of the chamber enclosedby the/tube. 41b into the tubeSdb andnso to the outlet 72a. If, for any-reason, the supply of liquid through the inlet pipe 52: increases unduly or out of proportion to .the vaporizing heat supplied, conditions change. For example, if there is a suddenly increased. demand, the pressure-in the outlet pipe 72a correspondingly d-ropsandliquid flows more. quickly from the pipe. 52 and flows in increased quantity down the inside of the wall-32b.- There being. asyet no corresponding increase in heatsupplied, some-of the liquid influx is not evaporated-and constitutes an excess; This liquid excess gathersby gravity in the bottom of the chamber enclosed by the Wall 3211 on the bottom plate 34bi If the-bottomof' thetube l-lb were open (like thetube 41, in. FIGURE l),-.the excess liquidwould rise outside of andwithin the tube 41b, forming a pool tending? to hamper gas flow and affording no signalof itspresence. Liquid gathering in the FIGURE 7 arrangement, if in a-small amount, can" flow upwardly through the small aperture 44b and can: be retained above the plate 43b-temporarily for evaporation subsequently when the gas flow may be diminished by lesser demand 'or'when there is'an' increase in heat supplied, the chamber within-thetube 41bactinglike a" surge chamber; Butrliquid gathering in the FIGURE 7 arrangement'under largefiow conditions and in substantialexcessquantities can flow only-with difiiculty up wardly, throughthe" small aperture 44b. Instead, most of "theliquid fiows and islifted (partly by gas lift entrain ment) directly up. the insidexofithepipe 55b. The pressure rise forces the liquid through the pipe 55b, from which it discharges by impingement onto the thermostat 1241; or into a cup 12515 in close proximity thereto. The thermostat is thus quickly cooled by the relatively cool excess liquid and promptly brings on the fire or increases the heat supply to cope with the enlarged demand. The thermostat continues to be substantially cooled until the pool of liquid in the cup 1251; has been evaporated. This is a predetermined quantity of liquid since any surplus overflows from the cup 125b into the tube 4112 from which it can be subsequently evaporated, as before. There is consequently assurance that the fire will be brought on full for at least a definite time. Gas generated flows from within the tube 4112 through the tube 54b and the cross 66b to the outlet pipe 72a in the usual way.

What is claimed is:

1. A liquid petroleum gas vaporizer comprising a vertical cylindrical jacket, a vaporized gas burner disposed to furnish products of combustion to travel upwardly through said jacket, a generally closed chamber having a side wall disposed vertically within said jacket, a tube disposed vertically within said chamber and generally closed at the upper and lower ends, means for supplying petroleum gas in liquid form to the upper end of said chamber to flow by gravity downwardly between said chamber wall and said tube and to be at least partially vaporized by said products of combustion into gas form, means opening into the upper region of said tube for conducting at least some of said vaporized gas to said burner, a thermostat extending into the upper region of said tube and at least in part responsive to temperature therein for controlling the flow of said vaporized gas through said gas conducting means, and a pipe opening through said lower end of said tube and extending within said tube into close relationship with said thermostat for conducting unvaporized liquid from beneath said lower end to the immediate vicinity of said thermostat.

2. A liquid petroleum gas vaporizer comprising a vertical cylindrical jacket, a vaporized gas burner disposed at the bottom of said jacket to furnish products of combustion to travel upwardly through said jacket, a generally closed chamber having a side wall disposed vertically Within said jacket, a tube disposed vertically within said chamber and generally closed at the upper and lower ends, mearis for supplying petroleum gas in liquid form to the upper end of said chamber to fiow by gravity downwardly between saidtube and said chamber wall and to be at least partially vaporized by heat from said products of combustion into gas form, a conduit opening into the upper region of said tube for conducting at least some of said varopized gas away, a pipe for conducting said gas from said conduit to said burner, a thermostat at least in part subject to temperature at the upper region of said tube for controllingfiow of said vaporized gas in said pipe between said tube and said burner, a pipe opening through said lower end of said tube and extending within said tube into close relationship with said thermostat, and means including an aperture in said lower end smaller than said pipe for admitting flow from beneath said lower plate into said tube.

3. A liquid petroleum gas vaporizer comprising a vertioal jacket, a vaporized gas burner disposed at the bottom of said jacket to furnish products of combustion to travel upwardly through said jacket, a generally closed chamber having a side wall disposed vertically within said jacket and exposed on its exterior to said products of combustion, a tube disposed vertically within said chamber and generally closed at the upper end and lower end, means for supplying petroleum gas in liquid form to the upper end of said chamber to flow by gravity downwardly over said tube and on the interior of said chamber and to be at least partially vaporized by heat from said products of combustion into gas form, a conduit open- 8 ing into the upper end of said tube for conducting at least some of said vaporized gas away, a pipe for conducting said gas from said conduit to said burner, a thermostat passing thorugh said jacket and through said chamber and in part subjectto temperautre in said chamber and also passing into said tube and in part subject to temperature in said tube for controlling the flow of said gas through said pipe, and a'pipe opening through said lower end of said tube and extending into close relationship with the part of said thermostat subject to temperature in 'said tube. j I

4. A liquid petroleum gas" vaporizer comprising a jacket, means for heating said jacket, a, generally closed chamber disposed vertically within said jacket and heated by said heating means, means for supplying petroleum gas in liquid form to the interior of said chamber, a tube vertically disposed within said chamber and generally closed at the upper and lower ends and having a predetermined inner diameter, a thermostat extending through said jacket and said chamber into the interior of said tube near the upper end thereof, means for connecting said thermostat to control said heating means, and a pipe having a diameter substantially smaller than said predetermined diameter opening through said lower end and extending into close relationship with said thermostat within said tube. a

5. A liquid petroleum gas vaporizer comprising a jacket, means for heating said jacket, a generally closed chamber disposed vertically within said jacket and heated by said heating means, means for supplying petroleum gas in liquid form to the interior of said chamber, a tube vertically disposed within said chamber and generally closed at the upper and lower ends, a thermostat extending through said jacket and said chamber into the interior of said tube near the upper end thereof, means for connecting said thermostat to control said heating means, a pipe opening through said lower end and extending into close relationship with said thermostat within said tube, and means including an aperture in said lower end for admitting flow from beneath said lower end into said tube.

References Cited in the file of this patent Ford Mar. 25, 1930 

5. A LIQUID PETROLEUM GAS VAPORIZER COMPRISING A JACKET, MEANS FOR HEATING SAID JACKET, A GENERALLY CLOSED CHAMBER DISPOSED VERTICSLLY WITHIN SAID JACKET AND HEATED BYP SAID HEATING MEANS, MEANS FR SUPPLYING PETROLEUM GAS IN LIQUID FORM TO THE INTERIOR OF SAID CHAMBER, A TUBE VERTICALLY DISPOSED WITHIN SAID CHAMBER AND GENERALLY CLOSED AT THE UPPER AND LOWER ENDS, A THERMOSTAT EXTENDING THROUGH SAID JACKET AND SAID CHAMBER INTO THE INTERIOR OF SAID TUBE NEAR THE UPPER END THEREOF, MEANS FOR CONNECTING SAID THERMOSTAT TO CONTROL SAID HEATING MEANS, CLOSE RELATIONSHIP WITH SAID THERMOSTAT WITHIN SAID TUBE, A PIPE OPENING THROUGH SAID LOWER END AND EXTENDING INTO AND MEANS INCLUDING AN APERTURE IN SAID LOWER END FOR ADMITTING FLOW FROM BENEATH SAID LWOER END INTO SAID TUBE. 